A corpora



F. M. sLouGH.

TELEPHONE SYSTEM.

APPLICATION FILED DEC. 22,1916. 1.3205716., Patented Nov. 4, 1919.

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.Sw www irs FFIQE@ FRANK 1VI. SLOUGH, OF ROCHESTER, NEW YORK, ASSIGNOR TO STROMBERG-CARLSON TELEPHONE MANUFACTURING COMPANY, 0F ROCHESTER, NW YORK, A CORPORA- TION OF NEW YORK.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Original application iled November 12, 1914, Serial No. 871,665, Patent No. 1,298,588. Divided and this application led December 22, 1916.

To all 'whom t may concern.'

. Be it known that I, FRANK M. SLOUGH, a citizen of the United States, residing at Rochester, in the county otl Monroe and State of New York, have invented certain new and useful Improvements in Telephone Systems; and I do hereby declare the tollowing to be a full, clear, and exact description of the invention, s uch as will enable others skilled in the art to which it appertains to make and use the same. p

My invention relates to improvements in telephone systems, and more particularly to manual common battery systems, though it is adapted for use in systems ot other types.

@ne of the objects of my invention is to provide means for preventing unnecessary disturbances in the operators telephone set in telephone systems employing an automatic disconnect arrangement. For example, where the talking strands of the line connectors are normally disconnected and means are provided for completing the strands, the act of completing the strands is apt to cause an electrical disturbance, such as a How of current through the operators receiver, which is strapped to her head, and which makes a very unpleasant and disagreeable sensation in herl ear, calcula-ted to interfere with the proper performance of her duty, and cause delay and other objectionable happenings in connection with the operation ot the system.

rIhese and other objects of my invention will appear from a description of an embodiment of the invention.

This application is a division of my application Ser. No. 871,665, filed Nov. 12, 1914, patented March 25, 1919, No. 1,298,588.

The ligure Shows diagrammatically a telephone system embodying my invention.

In the drawing a telephone line is shown at I, which will hereinafter be spoken of as the calling line, and a second telephone line is shown at II, which will hereinafter be spoken of as the called line. It will be understood that many tele-phone? lines lead to the exchange, illustrated diagrammatically here at III. I have illustrated but two of these lines, as they will be suiiicient to explain my invention. Means are provided at the main Station III for connecting telephone lines together, which is here shown as a cord circuit C. Suitable apparatus is provided for connecting the means C to the Serial No. 138,303.

telephone lines, here shown as switching apparatus S and S1. The apparatus SV is known as the answering switch and Sl as the calling switch. In the embodiment shown, these switches consist of an answering plug P, a calling plug P1, a jack J and a jack J1.

The line relays are shown at L, L1 and cut-oli relays at G, Gl. The automatic disconnect relay is shown at A, the listening key at B, the sleeve supervisory relays at I-I, II the tip supervisory relays at K, K1, the ringing relay at M, the ringing disconnect relay at VN and a ringing generator at Q. The subscribers apparatus on the calling line is shown at T and on the called line at T1.

In general, the operation of the system is as follows: The subscriber at T initiates acall, closing thei circuit of his line relay and operating his line signal. The operator inserts the plug P into the jack J and operates the listening key B, closing the contacts at 1 and completing a circuit for the relays A and D. The relay A closes its contacts, completing the cord circuit and the connection of the leads of the operators set to the cord. The relay D opens the circuit of the relay E, which releases its armature, whereupon the operators set F is connected to the cord. The relay E is slow acting, so that the operators set is not connected to the leads 2 and 3 until after the relay A has closed its contacts, so that no current can flow through the operators set until atter the disturbances caused by the actuation thereof have subsided. As soon as A has been operated, both the relays G and I-I will be operated; likewise, relay K in a well known manner. The relays K and H control the answering supervisory signal.

The operator then learns the subscriber desired (it being assumed that it is the subscriber at T1) and inserts the plug I)1 into the jack J1, operating a ringing key, for example, that at X. The relay M will be energized thro-ugh contacts of H1, which was energized when the calling switch was operated. The ringing takes place and continues until the subscriber responds, when it is interrupted by the relay N. The relay K1, will then be energized and conversation will take place. At the termination of the conversation the relays K and K,L will be deenergized and the operator will disconnect the cord from the lines. As soon as the subscriber at T retires, the relay K will be denergized, opening the circuit of the relay A through the contact 5, and the talking strand of the cord circuit will be auto matically interrupted.

lMore particularly, the operation of the system is as follows: When the subscriber' at T takes the receiver 6 from the hook 7, the switch `8 will be closed, lcompleting a circuit for the magnet L from ground 9-to battery 10-relay L-switch ll-line conductor 12-switch 8-13 6line conductor lllswitch l-to ground 16. The magnet of L will be energized, closing a'switch 17 and completing a circuit for the line lamp 18 through the battery 10, the switch 17'- lamp 18 and conductor 19. The lamp 13 is placed on the switchboard at the station TH before the operator and its illumination attracts the attention of the operator, who inserts the plug P into the jack J, the contacts 20 and 21 ofthe plug registering with the contacts 21 and 22', respectively,

key B, closing the switches 1-23 and 24.

of the jack. VThe operator then operates ythe The closing of the switch 1 completes a tem porary circuit for the magnets of the relays A and D, as follows: ground 25-battery 26#A.-switch l-D-to ground at 27. The energization of the magnet A will close l., the switches 30 and 31 in the talking strandsr of the cord circuit and connect the opera-.l

to-rs leads 2 and 3 through the now closed g switches 23 and 24 to the calling line. The??? energization of the magnet of the relay D i will cause it to open the switch 32 in the normally closed circuit of the relay E, causing the denergization of the relay E, which will release its armature, whereupon the switches 33 and 34 will be closed and connect the operators set F to the leads 2 and 3.

The relay E is lmade slow acting,'such as by the employment of suitable means, such as a piece of copper c. The relay E is normally energized over a circuit from ground at 27-through the switch 32-cnductor 35-winding of E-battery 36-to ground 37. The relay E being relatively slow acting, does not release its Aarmature and consequently the switches 33 and 34 do not open until after the expiration of an appreciable period of time during which the disturbances in the circuit connections caused by the op eration 0f A or B, or the closing of the switches 30 and'31 have been dissipated, sol that they do not flow through the operators receiver, which is not connected to the leads 2 and 3 at the switches 33 and 34 until after such disturbances have been dissipated.

At 40, 41 and 42 I illustrate junction points at which the leads of other cord circuits are connected to the set F. When the switches 301 andv 31 of the relay A were closed, circuits were completed for the relays (Jr, H and K. The circuit of the relays idle.

(i and H is as follows: ground 16-vwinding of G--2220-30-H-43-to ground at close the switches 53 and 5, opening the switch 54. The closing of the switch 5 completes a. circuit for ythe magnet of relay A independently of the switch 1. This circuit is as follows: 25-26-A-conductor 55u-switch -to ground 51. This circuit will be maintained as long as the relay K is energized, which will be as longas the subscriber T is on his line. V

r'The operator learns from the subscriber at T that it is the subscriber at T1 that 1s l desired, and after testing the called line in the usual manner, inserts the plug P1 into the jack J1, assuming vthat the called line was. A circuit will 'be completed forl the relay H, as follows: 44-43-winding of H1-conductor 60-contact 61-contact 62- winding of Gl-to ground The energiza- Ation of the winding of H1 closes the switches 64 and 65, completing the circuit of the magnet of the ringing relay M, as follows: ground (S6-'battery 67-switch 64 wind ing of M-conductor 68-contact X1-con ductor (S9-switch 50`to ground 51. The relay M will be energized, connecting the ringing current to the plug P1, as follows: through Q-X-conductor 70winding of N-switch Y1-conductor 72-contact 73 contact 74-the called line and back through the conductor GO-battery 67-to ground at 66. The winding of M also closes a switch 80, locking its circuit independently of the p contact X1.

When the subscriber at Tl responds, the closing of his substation bridge 82 reduces' the resistance of the ringing circuit so that sufficient current Hows to operate the magnet N, which opensthe switch 83 in the circuit of the magnet'of M, Vwhich releases its armature and the contacts Vcontrolled thereby are restored to the condition illustrated in the drawing. The relay K1 will now be energized over a circuit including the called line, which is as follows: `winding of K,-switch V65--conductor Z2-over the called line and back to the conductor 60- through the winding of H1--43 to ground at 44. The relay Kl controls the supervisory signal and the circuit of the relay M The system is now in condition for conversation between the subscribers at T and T1 and this takes place. When the subscriber at T hangs up his receiver hook, the circuit of the relay A, previously described, will be interrupted at the switch 5 and the magnet of the relay A denergized, whereupon the talking strands of the cord circuit are again interrupted at 30 and 31, and the line relay and line signal of the line I re` turned to the condition where they can be controlled by the subscriber T independently of the fact that the plug P is still in the jack J.

I have shown this particular -embodiment of my invention and the details thereof for the purpose of describing the invention. I do not wish to be limited to such embodiment or to such details, as numerous and eX- tensive departures may be' made from the form and details illustrated without departing from the spirit of the invention.

I claim 1. In a telephone system, a cord circuit including talking strands, operators set leads normally disconnected from said strands, switch means for connecting said leads to said strands, an operators set normally disconnected from said leads at normally open contacts, a relay magnet for causing said contacts to close to connect said set to said leads, a circuit local to the cord circuit adapted to be closed when said switch means is closed to cause said magnet to cause the connection of said set to said leads, and apparatus to delay the connection of said set to said leads until after said leads are connected to said strands. l

2. In a telephone system, the combination of an operators set and means to connect the operators set to the connecting means, apparatus to cause a How of an electrical charge in said means, a slow acting relay normally maintaining the operators set disconnected from the connecting means, a circuit or the slow acting relay and means to automatically denergize the slow acting relay when a call is answered and after the flow of electrical charge has ceased.

3. Y In a telephone system, the combination of a telephone line, a cord circuit having talking strands, an operators set and leads to connect said set to said strands, a slow releasing relay adapted when energized to operatively disassociate said set from said leads, an operators key adapted when operated to connect said leads to said strands, said slow releasing relay being always actuated when said leads are thus connected to said strands, and a relay having a circuit with contacts controlled by said key controlling said slow releasing relay and adapted when said key is closed to cause a -delayed operative association of said set with said leads.

4. In a telephone system, the combination of a cord circuit provided with normally open talking strands, a relay for controlling said strands, a listening key controlling said relay, an operators set whose connection to said strands is controlled by said key and means for delaying the connection of the operators set to the talking strands until after said relay has closed said strands.

5- In a telephone system, the combination of link connectors provided with normally open strands, a relay for controlling said strands, an operators set normally disconnected from said strands, a second relay controlling the connection of the operators set to said strands, said second relay being slow in action in comparison with the 'first named relay and a listening key controlling both said relays.

6. Iu a telephone system, the combination of link connectors provided with talking strands, an operators set and leads to connect the operators set to the talking strands, a relay having contacts in said leads, a second relay having normally open contacts in the leads of the operators set, a switch controlling both said relays, said second named relay being slow acting with respect to the rst-named relay, a locking circuit for the first-named relay and a subscriber-controlled relay controlling said locking` circuit.

7. In a telephone system, the combination of a cord circuit provided with talking strands, a relay having normally open contacts in said strands, an operators set and means to connectsaid set to said strands, apparatus to delay the connection of said set to said strands until after said relay has been operated and a subscriber-controlled relay controlling theI circuit of said relay.

8. In a telephone system, the combination of a cord circuit, automatic disconnect means for making and interrupting the the cord circuit, an operators set adapted to be connected to said cord, means to delay the connection of said set to said cord until the cord is completed and subscriber-controlled apparatus controlling said disconnect means.

9. In a telephone system, the combination of a cord circuit, provided with talking strands, a relay having normally open contacts in said strands, an operators set and leads to connect the set to said strands, a second relay, slow acting as compared with the first relay, having normally open strands in said leads, a listening key controlling both said relays, a circuit for the first named relay independent of said key and a supervisory relay controlling said circuit.

In witness whereof I have signed my name hereunto this 4th day of December,

FRANK M. SLOUGH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

